1. Field of the Invention
The present invention relates to a cylinder block structure for an engine.
2. Description of the Related Art
As shown in accompanying drawing FIG. 3, a cylinder head 100 for a general engine includes an intake port 101 and an exhaust port 102; and as shown in accompanying drawing FIG. 4 illustrating the general cylinder head taken along the line IV—IV of FIG. 3, water jackets 103 and 104 through which coolants circulates are formed in the cylinder head 100. Coolant circulating the water jackets 103 and 104 appropriately cools the cylinder head 100 to inhibit an excessive rise the temperature of the cylinder block and thereby avoid so-called seizure.
Walls between a bottom surface 106 of the cylinder head 100 and the water jacket 103 and between the bottom surface 106 and the water jacket 104, which walls respectively have thicknesses Tin and Tex in FIG. 4, are identical in thickness (i.e., Tin=Tex) as the illustration shows, so that the cylinder head 100 can be uniformly cooled.
Japanese Utility model No. SHO 64-51747 other than a technique described with reference FIGS. 3 and 4 discloses a technique of a cylinder head having a bottom surface a part of which is smaller in thickness than the remaining part, so that the thinner part is positively cooled with the object of prevention of generating a crack on the cylinder head.